Electric connectors are known comprising an insulating body made of plastic material and having a number of axial cavities housing respective electric terminals; and a recess formed in the rear end of the body, communicating with these cavities and housing a seal of elastomeric material having a number of openings respectively facing the cavities in the body for enabling assembly of the terminals inside the cavities. The openings normally comprise inner annular projections or lips, which are deformed radially during insertion of the terminals, and, after assembly, cooperate elastically with the terminal cables for insulating the inside of the connector from the outside environment.
FR-B-2407579 and FR-A-2602374 illustrate connectors of the aforementioned type wherein the openings in the seal also present transverse membranes pierceable by the terminals during assembly.
This solution provides for sealing against external agents in the event that not all the cavities are engaged by respective terminals, in which case the unused cavities are protected by the unpierced membranes.
A drawback of known connectors of the type briefly described above is that they fail to ensure optimum sealing of the cables, particularly when these are subject to flexing.
To improve sealing performance, connectors have been proposed with a seal having openings defining a conical inner sealing lip tapering in the insertion direction of the terminal, as illustrated in U.S. Pat. No. 4,460,227. Such a seal, however, is limited to connectors with a small number of terminals, and wherein the center distance between terminals is such as to permit openings having a much larger section than the related terminal, to prevent passage of the terminal through the conical sealing lip from expanding the lip against the walls of the opening, thus resulting in excessive mechanical, and particularly shearing, stress on the lip, in turn resulting, in extreme cases, in at least partial cutting of the lip.